Sri Lankan Journal of Applied Sciences

Optimizing Gene Selection: A Mini Review on Reference Gene Normalization for qRT-PCR in Solanaceae Plants

M. Hewadikaram — 2024-08-30

Gene expression analysis is fundamental for understanding biological processes, and quantitative real-time PCR (qRT-PCR) has become a widely used method for validating the expressions. Proper normalization across multiple samples and tissues is crucial for accurate and reliable results, requiring the selection of suitable reference genes for comparison with target genes. Finding internal reference genes in Solanaceae plants is crucial for precise transcript quantification using real-time PCR. Research on Solanaceae plants like Solanum rostratum, Solanum melongena, Solanum tuberosum, Solanum lycopersicum, Nicotiana tabacum, and Capsicum was conducted to identify reference genes for qRT-PCR normalization. Researchers can confidently assess gene expression variations in Solanaceae plants by establishing accurate reference genes, providing deeper insights into biological processes. This literature review provides a comprehensive overview of methodologies, challenges, and advancements in the selection of candidate reference genes for RT-PCR in Solanaceae plants. It has the potential to influence future research directions and methodologies, enhance scholarly discourse, and pursue excellence in molecular biology research.

Investigation of Lipase Producing Bacteria from Oil Contaminated Soil and Characterization of Lipase

J.A.D.D. Karunarathna — 2024-08-30

Hydrolytic enzymes such as lipases have emerged as key enzymes in a broad array of biotechnological industries due to their multifaceted characteristics. Many of the lipases that are currently in use in industry are of microbial origin. The aim of the present study was to isolate and identify lipase producing bacteria from oil contaminated soil and subsequent optimization of their culture conditions to maximize lipase production. Lipase producing bacterium Burkholderia sp. was isolated and identified by morphological studies, biochemical methods and 16S rDNA sequencing method. pH, incubation period, temperature, carbon source, nitrogen source and substrate concentration were studied to determine the optimum culture conditions for enzyme production. Media optimization studies showed that culture condition and media composition should be at pH 6, 30 °C, 48 hours of culture in a medium containing 2% olive oil as the main carbon source and yeast extract as the main nitrogen sources to maximize the production of lipase of Burkholderia sp. The crude enzyme exhibited hydrolytic activity in a wide range of temperatures (30 – 50 °C) and pH values (6–12), with an optimal temperature at 40° C and optimal pH at 8 with para-nitrophenyl palmitate as the substrate. Metal ions such as Cu2+, Mn2+ and Zn2+ inhibited lipase activity. The enzyme preferably acted on olive oil as a substrate. The results are a clear indication that Burkholderia sp. has a capacity to produce lipases and can be considered as a potential candidature for biotechnological applications.

Keywords: 16S rDNA sequencing, Burkholderia sp., Lipases, pNPP assay

Kappaphycus alvarezii Seaweed Powder Incorporated Dairy Ice Cream as a Potential Functional Food

D.C. Mudannayake — 2024-08-30

The demand for seaweed-based functional food products is significantly growing due to changes of lifestyles. This study aimed to evaluate the quality parameters of Kappaphycus alvarezii seaweed powder (SWP) incorporated ice cream developed as a novel functional food product with nutritious and therapeutical benefits. Fresh and cleaned seaweeds were oven-dried at 40°C for 48 h and ground to make a fine powder. The radical scavenging activity, total phenolic content and flavonoid content were performed for the dehydrated seaweed powder. Seaweed powder incorporated ice cream was developed with addition of seaweed powder (0, 0.2, 0.5, 1% w/w). Total phenolic content, flavonoid content and radical scavenging activity of dehydrated seaweed powder were 10.42 mg GAE g^-1, 15.51 mg rutin g^-1, 21.43%, respectively. Significant difference was observed for titratable acidity among four ice cream samples (p<0.05). The highest melting rates exhibited in 0.2% SWP incorporated ice cream sample. The 0.5% SWP incorporated ice cream was distinguished as the most acceptable ice cream. The 1% SWP incorporated ice cream sample was detected as the sample with highest hardness value. The highest DPPH radical scavenging activity was recorded in 0.2% SWP incorporated sample. In this respect, K. alvarezii can be successfully incorporated into ice cream as a rich source of antioxidants and sensory attributes.

Production of Low-cost Nanocellulose Bio Adsorbent for Water Purification

S.M.P.A. Koliyabandara — 2024-08-30

The present study presents a comprehensive investigation on the production of low-cost nanocellulose bio adsorbents for water purification. Nanocellulose samples were prepared from rice husk, pineapple leaves, and a composite of both materials. The effectiveness of these samples in removing Remazol Brilliant Blue (RBB) dye, a common water contaminant, was evaluated by studying the impact of contact time, adsorbent dosage, and pH value. The results demonstrated that the nanocellulose bio adsorbents possessed significant adsorption capacity for RBB, highlighting their potential for water purification applications. The nanocellulose bio adsorbent derived from using rice husk shown 57% removal efficiency and the nanocellulose derived from pineapple leaves shown 44% removal efficiency. The composite sample exhibited superior performance compared to the individual samples and it showed 62% removal efficiency, indicating a synergistic effect between rice husk and pineapple leaves. Reusability studies were performed in various runs, and it was confirmed that the nanocellulose bio adsorbents could be effectively recovered using the solvent NaOH and reused up to three runs to RBB in aqueous solutions with a considerable reduction in adsorption efficiency. This study demonstrates the promising capabilities of low-cost nanocellulose bio adsorbents derived from rice husk and pineapple leaves, both individually and in combination, as effective and sustainable alternatives for water purification.

Extraction of Natural Dye from Flowers and Dyeing Cotton

K. Vithushika — 2024-08-30

Flowers produce bright shade dyes due the presence of pigments such as anthocyanins, carotenoids and flavonoids. These pigments can be extracted in acidic, alkaline and neutral medium. Flowers such as Clitoria ternatea, Caesalpinia pulcherrima (Pink) and Tagetes erecta were selected for this study of dye extraction. The experiment was conducted in two factor factorial, complete randomized design (CRD) with three replicates. Microwave dried and crushed flowers were extracted in citric acid solution 5% (w/v), baking soda solution 5% (w/v) and water. Mordants such as, vinegar (20% v/v), baking soda 4% (w/v), salt 4% (w/v), cream of tartar 4% (w/v) and water were used to fix the extracted dye in the cotton fabric. Colour intensity of the dyed cloths was estimated from the lightness values obtained by colorimeter. The data were subjected to analysis of variance using SAS (9.1) software and the means were separated using Duncan’s multiple range test. Blue colour Clitoria ternatea flower gave blue, pink and dark green colour shades for aqueous, acidic and alkaline extracts, respectively. Caesalpinia pulcherrima produced purple, dark pink and brown shade colours for aqueous, citric acid and baking soda extracts, respectively. Tagetes erecta produced different shades of yellow colour for all the extracts. The results indicated that, pH influences in colour of the dyes extracted from flowers and the colour intensity of the dyed cloths vary according to both the extractants and the mordants used. The present study clearly revealed the potentialities of natural dye extraction and dyeing of fabrics using natural flowers.

Key words: Cotton, extractants, mordants, Flowers, natural dye.

Exploring the Potential of Organic Floral Preservative Solutions to Extend the Post-Harvest Life of Lotus (Nelumbo nucifera)

H.M.N.K. Rathnayake — 2024-08-30

Among aquatic plants Nelumbo nucifera (lotus) has a great economic significance to mankind by owning a considerable share in the local aquatic cut flower market. Lotus flower stem exudes a large quantity of sticky milky sap from the cut surface and latex coagulates on the cut surface which prevents or reduces water absorption and ultimately reducing flowers’ vase life. Vase life of flowers is one of the most crucial factors for cut flower marketing and commercialization. It can be improved by use of different preservatives substances. Compare to harmful chemical floral preservatives, botanical extracts are natural, safe and inexpensive compounds are always crucial in this respect for large scale applications. Hence, this study investigated the potential of some organic floral preservative solutions and its concentration on improving the vase life of lotus. Lotus were blanched in water bath at 40^oC for 30 seconds and placed for pulsing in 5% sugar solution for 30 minutes. Then the flowers were kept under different holding solutions at varying concentrations. 2%, 3% and 5% w/v concentrations of moringa and aloe vera solutions and 20%, 30% and 50 % v/v concentrations of coconut water were supplemented with 5% (v/v) vinegar. Two Factor Factorial Complete Randomized Experimental Design was used with five replicates, and Fisher’s Least Significant Difference test was done for mean separation. For the statistical analysis, SAS 9.4 version software was used. Physical properties and visual observations were made. The results proved that 30% (v/v) concentration of coconut water was best in prolonging the postharvest life of (10 days) lotus. The present study explored the potentialities of using organic floral preservatives to substitute the hazardous chemical preservatives to prolong the post-harvest life of lotus flowers.

Key words: floral preservatives, lotus, post-harvest life.

Exploring Low-Cost Adsorbents for Efficient Fluoride Removal

R.M.L.D. Rathnayake — 2024-08-30

Fluoride contamination in water poses a significant health risk, emphasizing the need for effective removal methods. This study examines the efficacy of low-cost adsorbents: Rice Husk (RH), Broken bricks (BB), and Activated Carbon (AC)—for fluoride removal. Batch experiments were conducted to characterize these adsorbents and evaluate their performance across varying pH levels. Results reveal a substantial impact of pH on fluoride removal efficiency, with RH, BB, and AC exhibiting optimal rates at pH 4, 2, and 6, respectively. This underscores the influence of pH-dependent surface charge characteristics and fluoride ion speciation on removal efficiencies. The results of competition studies revealed that the adsorbent BB demonstrates the highest affinity for fluoride ions compared to RH and AC suggesting that BB is more effective at adsorbing fluoride ions compared to the other adsorbents. Furthermore, analysis of adsorption kinetics and optimal dosages uncovers differences in adsorption mechanisms among the adsorbents. RH adheres to the Langmuir model, while BB follows the Freundlich model, and AC outperforms according to both models. These findings underscore variations in adsorption capacities, affinities, and mechanisms, with AC emerging as a promising option for efficient fluoride removal. Nonetheless, further research is necessary to fully comprehend the nuanced mechanisms behind pH-dependent fluoride removal and to explore potential pre-treatment strategies to enhance RH and BB's adsorption capacity. In summary, this study provides valuable insights into developing efficient fluoride removal strategies using economical adsorbents.

Determination of Glycaemic Index and Market Potential of Coconut Treacle as an Alternative Sweetener Among Young Adult Population in Sri Lanka

M.R.F. Litha — 2024-08-30

This study aimed to determine the glycaemic index (GI) and market potential of coconut treacle (CT) to assess its probability as a low GI alternative sweetener. A cross-sectional study was performed with 365 undergraduates to assess the market potential via Google Forms. Total sugar content was determined following AOAC guidelines. GI was determined using a standard clinical method in three separate sessions with 30 healthy individuals (18-26 years, 18.5-23.5kg/m2). In session-1, following an 8-hour fasting, blood glucose level (BGL) was measured. Then, participants consumed glucose and BGL was measured at 15^th, 30^th, 45^th, 60^th, 90^th, and 120^th minutes. The same procedure was repeated with CT in session-2 and session-3 (duplication). The majority of students (74.2%) preferred CT and 35.9% liked to consume CT for health benefits. Purity, texture, and taste were identified as important factors influencing purchasing decisions and 52.6% opted for supermarket purchases. More consumers (97%) exhibited adequate knowledge regarding the health attributes of CT and 72.6% perceived that CT can replace refined sugar. The total sugar was 66.68g per 100g and the GI of CT was calculated as 53.6. The study concluded that the CT belonged to the low GI category with a moderate amount of sugar.

Bio Solubilization of Eppawala Rock Phosphate (ERP) by Fungal-Bacterial Biofilm Action and its Effect on Crop Enhancement of Chili (Capsicum annuum)

A.P. Henagamage — 2024-08-30

Eppawala rock phosphate (ERP) has potential as a substitute for Triple Super Phosphate (TSP) due to its phosphorus content, but its low solubility limits its application. Recent research indicates that biofilms could enhance ERP's effectiveness by enhancing its solubility. This study evaluated the effectiveness of ERP solubilized through fungal bacterial biofilms (FBBs) and their impact on chili (Capsicum annuum) crop enhancement. Fungi and bacteria were isolated, screened for phosphate solubilization and develop FBBs, which were then tested for their phosphate-solubilizing ability with powdered ERP. The best FBBs was evaluated for its phosphate-solubilization with different CF combinations using a pot experiment with chili crop. The best biofilm, BF3, composed of Brevibacillus brevis and Penicillium polonicum, showed significantly greater phosphate solubilization capacity (P < 0.05), and the lowest medium pH. FTIR analysis of the biofilm-treated and untreated ERP samples showed significant changes in the intensity and positions of the phosphate bands, confirming their involvement in phosphate solubilization. Combining FBBs with ERP, especially when pretreated, significantly (P < 0.05) enhanced chlorophyll content, fresh weight and number of fruits of chili plants. It can be concluded that biofilm enriched ERP performs better compared to the DOA recommended TSP dosage in chili cultivation under controlled conditions.

Exploring Privacy and Security Concerns in Sri Lankan Telemedicine Systems: A Patient-Centric Self-Assessment

S. Vidanagamachchi — 2024-08-30

Due to rapid technological advancements, the field of telemedicine has flourished and gained widespread acceptance within the community. While telemedicine initiatives were introduced several decades ago, they struggled to gain prominence due to the prevailing availability of traditional healthcare facilities and a lack of mental preparedness for embracing digital health solutions. However, the recent years, particularly amid the COVID-19 pandemic, have witnessed resurgence in telemedicine practices, as they emerged as the sole dependable option for medical care. In an era where individuals are intricately intertwined with technology, especially when it comes to sensitive health-related information, it becomes imperative to possess a foundational understanding of security vulnerabilities and strategies for mitigating associated risks. Consequently, it becomes essential to undertake a comprehensive investigation focused on recognizing the privacy and security concerns inherent in Sri Lankan Telemedicine Systems. In pursuit of this objective, we have meticulously formulated a comprehensive questionnaire encompassing various facets of telemedicine practices. In order to ensure the credibility and applicability of our findings, our study enlisted real-world users of telemedicine applications as the sample population. Following an exhaustive phase of data collection, we subjected the gathered information to rigorous analysis, culminating in essential insights. These insights serve as a pivotal privacy and security guide for all users of telemedicine applications, offering them direction to enhance their practices, thereby fostering a healthcare service that is both secure and dependable.

Geospatial Analysis for choosing suitable location to start hotel in Sri Lanka Using Machine Learning

S. Nimesh — 2024-08-30

The post-pandemic recapture of Sri Lanka's tourist industry is anticipated, and this paper suggests a hotel that employs geospatial data science for strategic placement and operational excellence. The hotel will use geospatial analytics to choose the best site, customize its hospitality offerings to meet local demands, assign resources as efficiently as possible, build strong community relationships, and navigate the competitive marketplace. The hotel will succeed in the resurgent Sri Lankan hospitality sector cheers to its data-driven strategy.

Keywords: geospatial data science, hotel, Sri Lanka, Machine Learning